One of the three Marine special operations personnel killed in Helmand Province by an Afghan police commander on August 9th was a friend of a close friend of mine.

“I don’t even know what to think about this,” was his gut reaction to the news. “Too much raw anger and frustration right now.”

I think anger at the rogue Afghans and frustration as to why we are embroiled in such a futile conflict has many Americans scratching their heads and asking themselves why we’re still in Afghanistan. There have been at least 25 such “green on blue” shootings like this one since January, killing 31 U.S. and allied troops.

Nearly 11 years after we went into Afghanistan, it’s time we called a spade a spade, admit that we are fighting an endless and unwinnable war, and bring our sons and daughters back home.

With a broad and nebulous mission, a resilient and cunning enemy, restrictive rules of engagement, and an Afghan army and police force with dissidents turning their weapons on our troops, we face impossible odds. Combine this with the fact that we have broadcast our intent to leave the country in 2014, and the bottom line is clear: we have no chance of “winning” this war.

Our best option, at this juncture, is to bring our brave men and women home as safely and expeditiously as possible.

Our warriors have done everything asked of them, and more. They have deployed into harm’s way time and time again, leaving behind their brave and resolute families to struggle on in their absence. Many soldiers and Marines, particularly those in special operations and intelligence units with high operational tempos, have spent more time overseas in the last several years than they have back home. Their children have grown up without them, their husbands and wives have lived under constant uncertainty and fear, and their minds and bodies have endured more hardship than anyone deserves to bear.

How much sense does it make to delay our inevitable withdrawal until 2014?

The very forces we are attempting to train have killed dozens of our comrades, making our working relationship with the Afghan police and army one of acute contention and pervasive distrust. We can no longer trust the very forces we intend to train and empower to run the country when we leave. Whether the men that killed our troops were disgruntled local Afghans with a grudge against Americans or hard-core insurgents that infiltrated our ranks, the outcome is the same nonetheless. It is demoralizing to our forces. It makes us ask: “What are we still doing there?”

And if we can’t trust our Afghan counterparts, and must instead rely on “Guardian Angels” (i.e. armed Americans) to keep watch over any and all armed Afghans, why do we assume that these same Afghans should be entrusted to serve and protect after our departure?

There is no graceful way to bow out of this decade-long conflict.

We can do nothing and pull out our combat forces by 2015 as now planned. Or we can take a hard look at what’s happening and decide whether the cost in lives is worth the extra two years of anguish we’re sure to encounter if we stay in Afghanistan through 2014. Doing nothing and leaving our troops there is probably the “safest” political move, but this is a decision that calls for moral fortitude and leadership, not politics.

I think our country’s leadership would be well served to remember the Dalai Lama’s insistence that “in dealing with those who are undergoing great suffering, if you feel `burnout’ setting in, if you feel demoralized and exhausted, it is best, for the sake of everyone, to withdraw and restore yourself; the point is to have a long-term perspective.”

I’d say we’re demoralized and exhausted. When it comes to Afghanistan, perhaps it’s time to leave.